Aggregation in syntrophic communities

Last changed: 17 September 2021

The long-term ambition of this project is to understand the role of aggregation of syntrophic microorganisms that can inspire development of biotechnological solutions to improve the productivity in biogas processes.

Biogas production tackles climate change, while addressing several major environmental goals, such as improved waste management and recycling of nutrients to arable land. In the biogas system, thousands of different microorganisms are involved in the conversion of the organic material to methane (biogas). Of particular importance is syntrophic (cross-feeding) microorganisms that cooperate to degrade acids but there are barriers and challenges to these organisms reaching their full potential, which causes accumulation of acids (e.g. acetate, propionate) and restricts productivity and stability in the biogas process. The aim of this project is to overcome the restrictions related to syntrophic activity, by bringing microorganisms into close proximity in multicellular aggregates (often referred to as biofilms or flocs). Syntrophic aggregation (SYNAG) has fundamental importance for syntrophic activity, but there is still much to learn in this area.

Work in progress

At the moment we are conducting the first screening tests to decipher key microbial, environmental and physical factors that stimulate syntrophic aggregate formation and their links to acid degradation capacity. In parallel we currently develop anaerobic microfluidic systems and cultivations methods that enable real-time investigations and multivariate culture-based experiments. This will enable us to study the processes that underlie aggregate formation and evaluate how it is affected by various surrounding environmental factors. The long-term overarching goal of the project is to form a general model for aggregate development in syntrophic communities and to create a basis for novel process-design that will support key microorganisms and improve the productivity in biogas processes.

Real-time monitoring of the growth of syntrophic cultures
The first trial where we monitor the real-time growth of syntrophic cultures has been started
Factors that can affect aggregation and thus how quickly acids are degraded can be found in the surrounding environment for the bacteria, e.g. temperature, pH or toxic substances. There may also be purely microbial factors such as a "glue effect" between certain bacterial cells. There may also be added factors such as nanoparticles or nutrients.
Factors that can affect aggregation and thus how quickly acids are degraded can be found in the surrounding environment for the bacteria, e.g. temperature, pH or toxic substances. There may also be purely microbial factors such as a "glue effect" between certain bacterial cells. There may also be added factors such as nanoparticles or nutrients.
Illustration of the upscaling of an improved the biogas process
Our goal of the project is to create a basis for novel process-design that will support key microorganisms and improve the productivity in biogas processes.

This project is supported by the European Research Council (ERC) with the Starting grant No. 948138 and the by Swedish Research Council (VR) with the grant No. 2019-03846
Project start: 1 March 2021    Project duration: 5 years

 


Facts:

At SLU we work with the whole biogas chain. An unique feature for our research is that we answer questions about both energy generation and waste treatment. We have our own biogas plant as well as top modern laboratories.


Contact

Maria Westerholm Maria.Westerholm@slu.se

Associate professor, PhD
Swedish University of Agricultural Sciences
Department of Molecular Sciences